1. Field of the Invention
This invention concerns an apparatus for operating a pendulum of a twisting pendulum clock.
2. Description of the Prior Art
Conventional clocks counted time by operating a pendulum, but today when clocks using battery cells, crystals, tuning forks, etc., are developed, the pendulum has become quite unnecessary, as far as the function of the clock is concerned.
Nevertheless, the pendulum has now been re-evaluated as a means of confirming that the clock is working or as a means of decoration, and many clocks operated by battery cells, etc., which are provided with a pendulum are being manufactured. One apparatus which operates the pendulum in such clocks has the following construction: A rotor having protrusions along its outer circumference is fixed securely to a rotary shaft which rotates using one of the operating gears of the clock; a pendulum is suspended from the clock-movement-fitting top frame by a suspension wire; a connecting piece is provided in the middle of this pendulum suspension wire, and made connectable to the protrusion of said rotor; the connecting piece which connects to this protrusion is caused to revolve by the protrusion of the rotor which rotates by the rotation of the rotary shaft, thereby twisting the suspension wire to rotate the pendulum. In such an apparatus, impact and strong resistance may be applied to the rotary shaft by way of said rotor due to resistance of the pendulum, impact applied to the rotor when the twisted pendulum returns to its original position, and stoppage of pendulum motion when external impact is applied to the clock. As a result, the function and accuracy of the clock are adversely affected, thereby sometimes causing trouble to the clock. Therefore, when pendulum resistance and impact due to twisting of the pendulum are applied to said rotor or when the pendulum stops its motion, it is necessary to cause the rotor to slip on the rotary shaft to buffer the resistance of the pendulum, impact, etc.
One convenyional pendulum operating apparatus provided with a means to buffer such resistance, impact etc., has the following construction: A plate is fixed firmly to the rotary shaft; an idle wheel having protrusions along its outer circumference is idly fitted to said rotary shaft to cause the connecting piece to revolve; a spring is placed between the plate and the idle wheel, and its both ends are caused to come into contact with the plate and idle wheel elastically and under pressure; the rotation of the plate which rotates by the rotation of the rotary shaft is transferred to the idle wheel through frictional resistance of this spring, so that when said resistance, impact, etc., are applied to the idle wheel, the idle wheel is caused to slip and buffer the resistance and impact.
This conventional apparatus, however, poses various problems; namely, temperature changes cause changes in elastic pressure of the spring, and elastic pressure of the spring also becomes weaker due to aging changes in the spring arising from its long-term use; consequently, regular and satisfactory operations of the pendulum become unobtainable, the quality of clocks manufactured shows wide dispersion and clock assembling also becomes too complicated.